> For the complete documentation index, see [llms.txt](https://docs.fusion.vectra.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fusion.vectra.ai/detection-models/library/reconnaissance/xmastree.md).

# xmastree

**Explanation**

The xmastree NDM monitors network traffic for flows with XMAS Tree packets (FIN, PSH, and URG) which are typically associated with attackers attempting to evade detection or compromise the integrity of the network.

**What to Look For**

To identify potential xmastree activity on your network, look for flows with XMAS Tree packets (FIN, PSH, and URG) in your network traffic logs. Ensure that endpoint security software is installed and up-to-date on all hosts to protect against attacks. Investigate any abnormal activity associated with the xmastree NDM event and report it to the appropriate security teams for further analysis.

**Related MITRE ATT\&CK Categories**

[Discovery: Network Service Discovery, Technique T1046 - Enterprise](https://attack.mitre.org/techniques/T1046)

[Impact: Network Denial of Service, Technique T1498 - Enterprise](https://attack.mitre.org/techniques/T1498)

[Reconnaissance: Active Scanning, Technique T1595 - Enterprise](https://attack.mitre.org/techniques/T1595)


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